62 LEAF-CLIMBERS. Onar. IL 
These filaments or rudimentary leaves, as well as 
the petioles of the perfect leaves, whilst young, are 
highly sensitive on all sides to a touch. The slightest 
rub caused them to curve towards the rubbed side in 
about three minutes, and one bent itself into a ring 
in six minutes; they subsequently became straight. 
When, however, they have once completely clasped a 
stick, if this is removed, they do not straighten them- 
selves. The most remarkable fact, and one which I have 
observed in no other species of the genus, is that the 
filaments and the petioles of the young leaves, if they 
catch no object, after standing for some days in their 
original position, spontaneously and slowly oscillate a 
little from side to side, and then move towards the 
stem and clasp it. They likewise often become, after 
a time, in some degree spirally contracted. They 
therefore fully deserve to be called tendrils, as they 
are used for climbing, are sensitive to a touch, move 
spontaneously, and ultimately contract into a spire, 
though an imperfect one. The present species would 
have been classed amongst the tendril-bearers, had not 
these characters been confined to early youth. During 
maturity it is a true leaf-climber. 
Tropxolum azureum.—An upper internode made four 
revolutions, following the sun, at an average rate of 
lhr. 47m. The stem twined spirally round a 
support in the same irregular manner as that of the 
last species. Rudimentary leaves or filaments do not 
exist. The petioles of the young leaves are very 
sensitive: a single light rub with a twig caused one 
